For the holy spirit and we ourselves have favored adding no further burden to you except these necessary things

to keep abstaining from things sacrificed to idols, from blood, from what is strangled, and from sexual immorality. If you carefully keep yourselves from these things, you will prosper. Good health to you!

Thanks for your efforts to ask an on-topic question! It would help though if you went one step further and split your question into two – asking about the rationale for the JW view here (for example, "What is the basis for JW refusal of blood transfusions?), and then in a separate question asking about the Protestant rebuttal.
– Nathaniel♦Aug 18 '18 at 16:26

Hi @Kris - Thanks for pointing me to the JW.org faq. I am aware of what you have pointed to, but I am still at a loss other than what I put together in a possible answer. The scriptures referenced in the page linked talked about eating blood. There is nothing there about transfusions although I can see possible cross links. Can you try and come up with an answer to my question based on what you linked?
– Chris RogersAug 18 '18 at 22:13

3 Answers
3

As to your point about distinguishing between eating blood and medical usage of it I found a question from readers in 6-15-2004 Watchtower that was somewhat helpful particularly the portion below

Most people in ancient times would not have been troubled over the consuming of blood, as we can see from the writings of Tertullian (second and third centuries C.E.). Responding to false charges that Christians consumed blood, Tertullian mentioned tribes that sealed treaties by tasting blood. He also noted that “when a show is given in the arena, [some] with greedy thirst have caught the fresh blood of the guilty . . . as a cure for their epilepsy.”
Those practices (even if some Romans did them for health reasons) were wrong for Christians: “We do not include even animals’ blood in our natural diet,” wrote Tertullian. The Romans used food containing blood as a test of the integrity of real Christians. Tertullian added: “Now, I ask you, what sort of a thing is it, that when you are confident [that Christians] will turn with horror from animals’ blood, you should suppose them greedy for human blood?”
Today, few people would think that the laws of Almighty God are at issue if a physician suggested their taking blood. While Jehovah’s Witnesses certainly want to keep living, we are committed to obey Jehovah’s law on blood. What does this mean in the light of current medical practice?
As transfusions of whole blood became common after World War II, Jehovah’s Witnesses saw that this was contrary to God’s law —and we still believe that. Yet, medicine has changed over time. Today, most transfusions are not of whole blood but of one of its primary components: (1) red cells; (2) white cells; (3) platelets; (4) plasma (serum), the fluid part. Depending on the condition of the patient, physicians might prescribe red cells, white cells, platelets, or plasma. Transfusing these major components allows a single unit of blood to be divided among more patients. Jehovah’s Witnesses hold that accepting whole blood or any of those four primary components violates God’s law.

For details on the current guidelines for medical use of blood or its fractional components for Jehovah’s Witnesses see my answer to a related question

After the Flood, Jehovah told Noah and his sons: “Every moving animal that is alive may serve as food for you.” However, God set this restriction: “Only flesh with its life​—its blood—​you must not eat.” (Genesis 1:29; 9:3, 4) Clearly, Jehovah links very closely the life and the blood of a creature [...]

What if a Christian is badly injured or is in need of major surgery? Suppose doctors say that he must have a blood transfusion or he will die. Of course, the Christian would not want to die. In an effort to preserve God’s precious gift of life, he would accept other kinds of treatment that do not involve the misuse of blood. Hence, he would seek such medical attention if that is available and would accept a variety of alternatives to blood.

Would a Christian break God’s law just to stay alive a little longer in this system of things? Jesus said: “Whoever wants to save his life will lose it, but whoever loses his life for my sake will find it.” (Matthew 16:25) We do not want to die. But if we tried to save our present life by breaking God’s law, we would be in danger of losing everlasting life. We are wise, then, to put our trust in the rightness of God’s law, with full confidence that if we die from any cause, our Life-Giver will remember us in the resurrection and restore to us the precious gift of life.​—John 5:28, 29; Hebrews 11:6.

Jehovah's Witnesses also point out that for information on alternatives to blood transfusion, you must see the chapter entitled “Quality Alternatives to Transfusion” in the brochure How Can Blood Save Your Life? published by Jehovah’s Witnesses.

Here is an article published by Jehovah’s Witnesses that explains their basis for refusing to have whole blood transfused:

What Does the Bible Say About Blood Transfusions? (See NOTE 1) The Bible commands that we not ingest blood. So we should not accept whole blood or its primary components in any form, whether offered as food or as a transfusion. Note the following scriptures:

Genesis 9:4. God allowed Noah and his family to add animal flesh to their diet after the Flood but commanded them not to eat the blood. God told Noah: “Only flesh with its soul—its blood—you must not eat.” This command applies to all mankind from that time on because all are descendants of Noah.

Leviticus 17:14. “You must not eat the blood of any sort of flesh, because the soul of every sort of flesh is its blood. Anyone eating it will be cut off.” God viewed the soul, or life, as being in the blood and belonging to him. Although this law was given only to the nation of Israel, it shows how seriously God viewed the law against eating blood.

Acts 15:20. “Abstain . . . from blood.” God gave Christians the same command that he had given to Noah. History shows that early Christians refused to consume whole blood or even to use it for medical reasons.
Why does God command us to abstain from blood? There are sound medical reasons to avoid blood transfusions. More important, though, God commands that we abstain from blood because what it represents is sacred to him.—Leviticus 17:11; Colossians 1:20. (See NOTE 2)
Source: https://www.jw.org/en/bible-teachings/questions/bible-about-blood-transfusion/